双连梁短肢剪力墙结构非线性随机演化分析

Nonlinear Stochastic Evolution Analysis of Shortleg Shear Walls with Dual Binding Beams

摘要:

在混凝土随机损伤力学研究的基本框架内,基于混凝土弹塑性损伤本构模型和概率密度演化理论,从荷载位移曲线、混凝土和钢筋应变、混凝土损伤和截面内力几个方面对双连梁短肢剪力墙结构进行了分析.分别通过样本轨道、系综数值特征和概率密度三种方式描述了结构非线性随机演化力学行为.研究表明,在结构不同层次的反应中,出现了概率密度曲面“多脊”和“多峰”的复杂演化现象,混凝土非线性与随机性耦合使得结构不同层次的反应变得复杂多样.研究同时发现,在结构受力行为演化过程中,随机性与确定性之间可以互相转化.

关键词:双连梁短肢剪力墙; 非线性随机演化; 弹塑性损伤本构; 概率密度演化方法

Abstract:

Based on an energy release ratebased plasticdamage model and probability density evolution method (PDEM),an investigation of the shortleg shear walls with dual binding beams is conducted on the Pcures,concrete and reinforcement strains,concrete damages and crosssectional internal forces in the frame of stochastic damage mechanics for concrete.Nonlinear stochastic evolution of structures is described through sample tracks,ensemble numerical characteristics and probability density.Multipeaks and multiridges phenomenon appear in probability density function evolution surfaces of the different response level,which roots in couple of randomicity and nonlinearity.It can also be concluded that randomicity and certainty may transform into each other in the process of structural response evolution.

Key words:shortleg shear walls with dual binding beams; nonlinear stochastic evolution; plasticdamage model; probability density evolution method